Grease and the method of preparing the same



Jan 21, 1.941- L c. BRuNsTRuM E'rAL 2,229,363

GREASE AND THE METHODOF PREPARING THE SAME Filed April 29, '1940 2sheets-sheet@ .F15/ UIL l FT'YCS @LYCEE/NE DIST/LED Jan. 2l, 1941. L. c.BRUNsTRuM Erm.

GREASE `AND THE METHOD 0F PREPARING THE SAME Filed April 29', 1940 2Sheets-Sheet 2 Patented Jan. 21, 1941 UNITED STATES GREASE AND- THEMETHOD F PREPARING THE SAME Lawrence C. Chicago, lll., and Re en I A.Swenson, Whiting, Ind., assignors to Standard 0il Company, Chicago,Ill., a corporation of Application April 29, 1940, Serial No. 332,200

14 Claims.

This invention relates to improvements in lubricants and moreparticularly to improvements in greases for use under conditions of hightemperature and pressure and to the method of preparing the same.

The compositions of the present invention are particularly adapted forlubricants such as mill greases, gear shields, skid greases and thelike. Mill greases are used in lubricating large open bearings wherehigh temperatures and shock loading are frequently encountered.' Suchgreases are usually employed for the lubrication of bearings on steelcalender rolls and other rolls in paper mills, tube and hammer mills forpulverizing cement, coal, ores and the like. Mill greases are alsofrequently used to lubricate heavy open shafting subjected to hightemperatures. Gear shields are heavy gear lubricants used to lubricatelarge open pinions and spray cooled worm drives generally used in steelVrolling mills and the like. Skid greases are lubricants employed tolubricate the skids forming the hot beds in rail mills iand the like.

It is an object of the present invention-to pro vide a lubricant havinga high softening time for the soap content thereof.

Another object of the invention is to provide a lubricant which can bemolded into cohesive tough blocks capable of withstanding shock loading.

A further object is to provide a grease cake which is oily and unctuouswhen rubbed or worked and which is capable of being worked Without amaterial change in consistency.

Another object of the present invention is to provide a grease which ishighly resistant to high temperatures, which does not leak oil at hightemperatures and which do'es not carbonize.

Still another object of the invention is to provide a grease which willstick tenaciously to open gears at high temperatures.

Other objects and advantages of the present invention will becomeapparent from the following description thereof, and the accompanying 45drawings which form a part of this specification,

and in which Figure 1 is a flow diagram showing the source of theessential ingredient of our greases, and

Figure 2 is a chart showing the' fatty acid composition of thismaterial.

We have discovered that a. lubricant having the above stated desirableproperties can be obtained by preparing a grease in which the fattymaterials usually employed for forming the soap portion of the grease isreplaced by the pitch obtained from the distillation of hydrogenatedfish oils. The source of this material is shown by the ow diagram ofFigure l accompanying this specication. The fish oil which may be used,for i0 example sardine cil, herring, cod, menhaden and the like, isfirst split by any of the Well known methods to produce glycerine andfatty acids. After separation-of the glycerine -the fatty acids arehydrogenated and the hydrogenated fatty acids subsequently distilled toproduce an overhead distillate of hydrogenated sh oil fatty acids and a`residue referred to herein as No. 1 pitch. The No. 1 pitch inwhich areconcentrated some fatty materials may be used as such for our purposes.However, it is preferred to submit the No. 1 pitch to a splittingoperation to produce more glycerine and hydrogenated fatty acids.` Afterseparation of the glycerine the hydrogenated fatty acids are distilledto produce an overhead product of hydrogenated fish oil fatty acidslwhich may be combined with the distillate from the first distillation.The residue resulting from the second distillation is the material weprefer to use and is referred to herein as No. 2 pitch.

These pitches although commonly referred to as stearine pitch are not tobe confused with the tarry, fatty acid pitches obtainedby the distilla--tion of animal or vegetable fatty materials. The pitch obtained as aresidue in the distillation of hydrogenated iish oils is distinguishedfrom the so'called stearine pitches from animal and vegetable fattymaterials in that the latter are unsaturated, relatively high inunsaponiable matter, and decient in fatty acids aboveCia. In con- -trastthe pitches obtained from distillation of hydrogenated fish oils aresaturated, rich in C20, C22, C24 and higher molecular Weight fattyacids, and are relatively poor in unsaponiable matter. These pitchescontain at least 65% of C20 to C24 and higher fatty acids. Stearinepitches obtained in the distillation of vegetable and animal fats are adark, tarry material whereas the pitches obtained from the distillationof hydrogenated fish oil are crystalline in structure and are of arelatively light color.

The inspections on representative samples of No. 1 pitch and No. 2 pitchare given in Table I below. w

. TABLE I Constants on stearine pitch lNo.1ptch No.2pitch Sa niiicationo., mgm. KOH/gm 151 152.6 Frlfatty acid (oleic), percent 16. 6 18.4 10.515.3 Total fatty acid, percent 3 86. 5 86. 3 Fat, percent 79.7 79.7 79.374. 2 Neutralization No. (acids) mmn.KOH/gm. 178v 177Moisture-insolubleunsaponitablemercent. 4. 3 3.9 10.4 11.8 Iodine value(Hanns) .'4. 2 5.6 Melting point, F o8.8 75. 6 59 (l 8.0

content and an extremely low iodine value. Thisl pitch as indicated byyits low iodine value is as saturated as double pressed stearic acid. Thehigh total fatty acid content of these pitches-as compared to the fattyacid content of not substantially more than about for the so-calledstearine pitches from animal and vegetable fats makes the formervaluable as a soap stock for grease making.

The composition of the No. 1 and No. 2 pitches and the composition ofthe distilled hydrogenated sh oil fatty acids is given in Table No. 2.

TABLE II Composition of fatty acids The data of Table II are graphicallyrepresented in Figure 2 accompanying the specification. Asnoted from theabove data the-No. 1 pitch and the-No. 2 pitch are rich in C20 to.C22fatty acids. Y

Broadly our invention comprises greases in which the soap base isprepared by saponifying pitch obtained from the distillation ofhydrogenated sh oils with caustic soda. Greases of the hereinbeforestated types in general are prepared from soda soaps and soda rosinsoaps and may, if desired, contain a ller such as asbestos mica,graphite, talc and the like.

These greases have the following approximate composition by weightpercent:

Per cent Soda soap of hydrogenated fish oil fatty acid pitch 1.0 to 30.0Soda rosin soap 1.0 to 30.0 Oil v 30.0to98.0 Filler 0.0' fto 30.0

The ratio of soda rosin soap to the soda pitch soap may be variedrespectively from about 1:10

Our invention may be understood from the following examples which aregiven by Way of illustration and are not to be construed as limiting thescope of the invention.

EXAMPLE I A mill grease made from the following ingredients in thefollowing approximate proportions: y

Pounds Hydrogenated fish oil fatty acid No. 2 pitch- 15.6 Rosin-oil 25.7Dry sodium hydroxide 3.57 Mineral oil 55.93

' droxide in a 48 Baum solution then added.

approximate proportions:

hour or longeruntilfoaming ceases and the remaining portion of therosin-oil added. 'I'he mixture is maintained at a temperature of about320 F. to about 350 F. for about two hours during which period thealkalinity of the base is adjusted to 0.05% to 0.1% sodium hydroxide.'Ihe balance of the required amount of mineral oil is then graded in andthe temperature raised'to about 400 F. to 425 F. and maintained at thistemperature for about 15 minutes. The grease is then filled into watercooled pans to solidify the grease. After the grease has solidified itis then cut into cakes of the desired size.

The term rosin-oil identifies throughout the specification and claims acomposition used in preparing the above grease, as well as the greaseshereinafter described, and is a mixture of about 50% rosin acid andabout 50%.mineral oil.

'I'he above grease has the following approximate composition:

Per cent by weight Soda soap of hydrogenated fish oil fatty aid pitch14.04 Soda rosin soap 13.62 oil 72.34

Although the total soap content of the above grease is about 27% and theratio of the soda rosin soap to the soda soap of No. 2 pitch is about1:1 this ratio may be varied from 1:10 parts of the soda rosin soap to10:1 parts of the soda soap of No. 2 pitch, and the soap content may bevaried -from about 10% to about 50% to obtain products EXAMPLE 2 Agrease suitable for use as a heavy gear shield lubricant is preparedusing soda, pitch soap in place of the soda fatty acid soap usuallyemployed in preparing such greases. This grease is made from thefollowing ingredients in the following Pounds Hydrogenated fish oilfatty acid No. 2 pitch- 2.6 Rosin-oil 4.0 Dry sodium hydroxide .54 Airfloated asbestos 25.0 Petroleum oil 67.98

'Ihis grease Will have the following approximate composition:

Per cent by weight acid pitch '2-.34 Soda rosin soap 2.12 Air iioatedasbestos 25.00 Oil 70.54

In the preparation of this grease all of the No. 2 pitch in an amount ofoil equivalent to two and one-half times the amount of pitch is chargedto a mixer and the contents heated until the pitch is completely melted.All of 'the sodium hydrox. ide in a 48`Baurr1 solution is then added ata temperature of about 150 F. to about 200 F. I'he temperature is thenraised to about 235 to 250 F. and maintained at this temperature forabout 3 hours until saponication is completed. During this period smallamounts of water are addedintermittently. After the 3 hoursaponiflcation period more heat is applied to the mixer andsubstantially al1 of the water driven out of -the soda soap base. Allofthe rosin-oil is then slowly added and heating continued until thesoap base is again dry. At this point the alkalinity of the mix isadjusted to 0.03% to about 0.1% sodium hydroxide and aboutone-half ofthe balance of the oil graded in. After this portion of the oil has beengraded in the asbestos is added and stirring continued until the batchis smooth. After all of the asbestos has been added the balance of theoil is graded in and the batch stirred at a temperature of about 200 F.to about 225 F. 'I'he batch is then ready for lling.

As shown above the total soap content of the grease is about 4% and theratio of soda rosin soap to the soda pitch soap is about 1:1. However,the soap content 1% to about 30% to obtain greases of this type havingvarious consistencies, and the ratio of the soda rosin soap to the sodapitch soap may be varied in the ratio of from about 1:10 `parts of sodarosin soap to 10:1 parts respectively of the soda pitch soap. While theoil used in the above example has a Saybolt Universal viscosity at 210F. at about 125 seconds, oil ranging in viscosities from 50 seconds to400 seconds at 210 F. Saybolt Universal may be used.

Greases of this type possess unusual heat resistant properties andadhere well to gear teeth even at high temperatures.

EXAMPLE 3 A skid grease having a-consistency that permits it to beapplied to the skids by means of a mechanical dispensing system andhaving the following approximate composition:

Per cent by weight Soda soap Vof hydrogenated fish oil fatty The greaseis prepared in substantially the same manner as was the gear shieldlubricant described in Example 2. While the total soap content of thefinished grease is about 3.0% and the ratio of soda rosin soap to thesoda pitch soap is 1:1, the soap content may be varied from 0.1%, whichcontent produces an appreciable thickening effe-:r of the oil, to such asoap percentage that the grease is no longer dispensable by mechanicaldispensing equipment. The ratio of soda rosin soap to the soda` mitchsoap may also be varied in order to obtaingreases of various properties.Thus the ratio of the soda rosin soap to the soda Ditch soap may bevaried from 1:10 parts to 10:1 parts respectively. The oil used inpreparing a grease of the aboveformula is one having a Saybolt Universalviscosity at may be varied from about to about 30.0%

100 F. of about 900 seconds. viscosity may b e varied from a viscosityat 100 F. of about 80 seconds to a Saybolt Universal viscosity at 210 F.of about 300 seconds. This skid grease is a smooth buttery grease whichspreads well when contacted by the hot rail or billet. It is highly heatresistant and does not -flow when subjected to high ternperatures and issuiliciently non-inflammable so that it does not ash when contacted byrails or billets that are at red heat. L

Wherever used in the specification and claims the term pitch refers tothe pitch obtained by the distillation of hydrogenated sh oil fattyacids and the term soda pitch soap refers to However, the oil the sodiumsoap of the hydrogenated fish oil fatty acid pitch.

While the present invention has been described and illustrated withrespect to preferred embodiments thereof the same are not to beconsidered as limiting the scope of the invention except insofar asdefined by the appended claims.

We claim:

1. A heat resistant grease comprising a lubricating oil, soda rosin soapand soda soap of hydrogenated sh oil fatty -acid pitch.

2l A heat resistant grease comprising a lubricating oil,'soda rosinsoap, a filler and soda soap Vof hydrogenated fsh oil fatty acid pitch.

3. A heat resistant grease comprising from about '1.0% to about 30.0% ofsoda rosin soap and from about 1.0% to about 30.0% soda soap ofhydrogenatedll fish oil fatty acid pitch and a ,lubricating oil.,

comprising thel following approximate composi tion:

. Per cent Soda soap of hydrogenated fish oil fatty acid pitch 1.0 tov30 Soda rosin soap 1.0 to 30` 011--; .4 30.0 to 98 Filler 0.0 to 30 6.vA'heavy gear shield lubricant resistant to high temperatures comprisinga soda soap of hydrogenated lsh oil fatty acid pitch, soda rosin soap,asbestos' and a lubricating oil, the total soap content of said greaseranging'from'about 1.0% and the ratio? of the soda rosin soap to thesoda soap of hydrogenated sh oil fatty acid pitch varying in the ratioof from about 1:10 to 10:1 respectively.

7. A heavy gear shield lubricant resistant to high temperaturescomprising the following .approximate composition:

` Per cent by weight Soda soap of hydrogenated fish oil fatty acid pitchSoda rosin soap 2.12 Air oated asbestos 25.00

Petroleum oil 70.54

Saybolt Universal soA mate proportions:

"pitch, heating the mixture 9. A mill grease having the followingapproximate composition:

Per cent by weight Soda soap of hydrogenated fish oil fatty acid pitch I1 Soda rosin soap 13.62 Mineral oil 72.34

10. A skid grease resistant to high temperatures and capable of beingmechanically dispensed comprising the following approximate composition:

11. A method of preparing a heat resistant heavy gear shield lubricantprepared `from the following ingredients in the following approxi-Petroleum oil Pounds Hydrogenated iish oil fatty acid pitch- 2.60Rosin-oil 4.00 Dry sodium hydroxide .54 Air oated asbestos 25.00Petroleum n 67.98

comprising mixing all of the hydrogenated ilsh oil fatty acid pitch inan amount of oil equivalent tov about two and one-half times the amountof until all the pitch is completely melted, adding all of the sodiumhydroxide in a 48 Baume solution to said mixture at a temperature toabout 150 F. to about 200 F., raising the temperature to about 235 F. toabout 250 F. and maintaining the mixture at this temperature for aboutthree hours until saponiiication is completed, adding small amounts ofwater to said mixture during said saponliication period, increasing thetemperature after saponication of the hydrogenated lsh oil fatty acidpitch to removesubstantially all of the water. adding all of therosin-oil" to the mixture and heating` the same until dry, adjusting thealkalinity of the mixture to about 0.03% to about 0.1% sodium hydroxide,grading in about one-l half the balance of the oil and all of theasbestos. stirring the mixture until smooth and nnally grading in theremaining portion of the oil at a= temperature of about 200 F. to about225 F.

12. A method of preparing a heat resistant mill grease prepared from thefollowing ingredients in the following approximate proportions:

Pounds Hydrogenated fish oil fatty acid.pitch 15.6 Rosin-oil y '1 25.7Dry sodium hydroxide 8.57 Mineral nii' 55.93

comprising mixing all of the pitch and an amount of mineral oil equal toabout one and one-half times the amount of pitch at a temperature ofabout 170 F. to about 270 F. until the pitch is completely melted.adding all of the sodium hydroxide in a 48 Baume solution, adding tosaid mixture two-thirds of the required resin-oi and heating the mixtureto a temperature of about 220 F. to about 250 F. until substantially allof the water is driven out, raising the temperature to about 320 F. toabout 350 F. and maintaining the same at this temperature until foamingceases and then adding the remaining por- 'tion of the rosin-oil,maintaining the temperature at about 320 F. to about 350 F. for abouttwo hours while adjusting the alkalinity of the mixture to about 0.05%to about 0.1% sodium hydroxide, grading in the balance of the mineraloil, raising the mixture to a temperature of about 400 F. to about 425F. and maintaining the same at said temperature for about 15 minutes andsubsequently filling the mixture into watercooled pans to solidify thegrease.

13. The method of preparing a heat resistant grease comprising thefollowing ingredients:

Hydrogenated :ilsh oil fatty acid pitch Rosin-ou" Mineral oil, and

Sodium hydroxide comprising mixing all oi' the hydrogeated fish oilfatty acid pitchwith an amount of mineral to from about one and one-halftimes to about two and one-half times the amount of pitch, heating themixture to a temperature sufficient to melt all of the pitch, adding allof the sodium hydroxide in a 48 Baume solution, raising the temperatureof the mixture to about 235 F. to 250 F., adding the rosin-o adjustingthealkalinityof the mixture to about 0.05% to about 0.1% sodiumhydroxide and subsequently grading in the balance of the mineral oil.

14. A grease comprising a lubricating oil, soda rosin soap, and a sodasoap of hydrogenated fish oil fatty acid pitch.

LAWRENCE C. BRUNSTRUM. f REUBEN A. SWENSON.

